21640720

素因数分解:

$2^4\times 5^1\times {\mathrm{270509}}^1$

素因数の和:270522

約数の個数: 20

約数和(自身を含む): 50314860

約数和(自身を除く): 28674140

約数列:

[1, 2, 4, 5, 8, 10, 16, 20, 40, 80, 270509, 541018, 1082036, 1352545, 2164072, 2705090, 4328144, 5410180, 10820360, 21640720]

約数ペア:

[(1, 21640720), (2, 10820360), (4, 5410180), (5, 4328144), (8, 2705090), (10, 2164072), (16, 1352545), (20, 1082036), (40, 541018), (80, 270509)]